Can you please tell me that National Institute of Open Schooling is a recognized board or not? Is it applicable for entrance exams?

[Vinodt]

Yes, National Institute of Open Schooling (NIOS) is a recognized board like ICSE,CBSE and it is applicable for entrance exams.

The National Institute of Open Schooling (NIOS) formerly known as National Open School (NOS) was established in November,1989 as an autonomous organisation in pursuance of National Policy on Education 1986 by the Ministry of Human Resource Development (MHRD), Government of India.
NIOS is providing a number of Vocational, Life Enrichment and community oriented courses besides General and Academic Courses at Secondary and Senior Secondary level. It also offers Elementary level Courses through its Open Basic Education Programmes.
NIOS is the largest open schooling system in the world.

[Rahul Parik]

The National Institute of Open Schooling (N.I.O.S) is an autonomous organization

It is set up by the Ministry of Human Resource Development, Government of India, in 1989

Yes, the NIOS board is recognized by all universities and education institution in India

It is the largest open school in the world.

The National Open School is a government authorized board.

It also runs Open Basic Education Programmes through Distance Education Mode at the Elementary stage

Courses offered by NIOS
NIOS offer the following courses:
• Open Basic Education Programme, Which includes following three levels courses
• OBE 'A' Level Course—Equivalent to class III
• OBE 'B' Level Course—Equivalent to class V
• OBE 'C' Level Course—Equivalent to class VIII
• Secondary Course—Equivalent to class X
• Senior Secondary Course—Equivalent to class XII
• Vocational Education Courses
• Life Enrichment Programmes

Here I am uploading the PDF file which includes the List of Universities/Institutions Recognizing NIOS Exam & Certification

List of Universities/Institutions Recognizing NIOS Exam & Certification